Air-pump.



C. B. DALZELL.

AIE PUMP.

APPLXGATION FILED MAY 26,1909.

Patented Mar. 15,1910.

2 sHBETsf-SHEBT 1.

aval C. B. DALZELL.

AIR PUMP.

APPLICATION FILED MAY 26,1909.

Patented Mar. 15, 1910,

2 SHEETS-SHEET 2.

' durable construction and involves erases i.

CHARLES B. DALZELL, LITTLE FALLS, NE'W YORK, ASSIGNOR TO D. H. BURRELL8c COMPANY, OF LITTLE FALLS, NEWT YORK.

AIR-PUMP.

Specification of Letters Patent.

itatenieu atar. i5, itil-til.

Application filed May 26, 1909. Serial No. 498,497.

To all who/m it may concern:

Be it knownl that I, `CHARLES B. DALZELL, a citizen otl the United'States, residing at Little Falls, in the .'connty of Herkimer and Stateof New York,l haveiiivented a new and useful improvement in Air-Pumps,ot which the following is a specification.

rlfhis invention relates more particularly to improvements invacuumtpumps and has for one ot its objects to`prodnce an efficient andAdesirablel pump which is of simple and the minimum number of parts.

Other objects of the invention are to so construct the pump that accesscan be readily had to the working parts thereof, vand that the valvescan be quickly and easily removed, or the pump taken apart for cleaning,repairing or replacing any of the parts thereof without disturbing thepipe connections; and also to so construct and arrange the valves andtheir operating mechanism that while the operating mechanism is mainlyinclosed in the pump casing, where it can be kept clean and thoroughlylubri: cated, the connections between the valves and their operatingmechanism are located so as to be accessible and allow the valves to beremoved and replaced with the least delay and" orlt.

In the accompanying drawings,consisting of two sheets: Figure l is alongitudinal sectional elevation oi a vacuum pump embodying theinvention. Fig. 2 is a sectional plan of the base 'thereof in line 2-2,Fig. 1. Figa v3 is a transverse sectio;\al elevation of the pump in line3 8, Fig. l. Fig. i is an end elevation thereof, partly in section, inline LH-4, Fig. l. Fig. 5 is a perspective view et' the valves detached.Fig. 6 is a fragmentary end elevation of the pump.

Like reference characters refer to like parts in the several figures. i

A multiple cylinder pump is shown in the drawings. A and A represent thecylinders, B and B the pistons, C the crank shaft having opposite crailkportions connected to the pistons by pitmen D and D, andl E and E arecombined inlet and outlet valves for the cylinders A and A,respectively.

The pump casing or body comprises base, intermediate and top sections a,a and a2, respectively, which are separate from each other and arebolted or otherwise detachably semired together. The cylinders A A are.

formed in the intermediate section a. Their' lower ends are closed bythe base section c and their upper ends open into a crank chamber cformed by the upper end ofthe intermediate section and the top sectionu2. An opening 'c3 is provided in the top ot the casing through whichaccess can be had to the crank chamber and cylinders, and which isclosed. by a loose cover plate 0.,

The crank shaft C is journaled at its ends in bearings c at the oppositesides ot the casing, formed partly by the intcwncdiate section c. andpartly by the top section a, so that the crank shaft is released andwith the pistons can be littcd out oi the casing when the top section (E:is removed.

The valves E 'and E', which are o the oscillating piston type, arearranged end to end in a cylindrical chamber or opening E2 which extendsthrough the base a parallel with the c 1ank shaft and is open at itsopposite ends. The valves are of uniform` diameter' throughout theirlength and can be inserted into and removed froml the valve chamberthrough the open ends thereof. This valve chamber is located beneath andin close proximity to the cylinders A A and communicates with eachcylinder through ports c and e controlled by the valves E and lC. In theposition ot the valves shown in the drawings, which they occupy when thepistons are at the ends oi their strokes, the ports @and c are closed.By rocking the valves in one direction'from this position, notches e2therein connect the ports c with an inlet passage j' in the base toadmit the air to the cylinders, while by rocking the valves in theopposite direction, notches c therein connect the ports c with an outletpassage f in the base to exhaust the cylinders. Thus both the inlet ot'air to and the outlet of air from each cylinder is` controlled by asingle oscillating valve. IThe inlet and outlet passages f and f leadrespectively to inlet and outlet pipesF and F which are connected to thebase section o, of the pump casing.

The valves are operated by cams G G which are secured to the ends of thecrank shaft within the crank chamber c and bear against antifrictionrollers 'at the upper ends Y ofl vertical push rods g and gf, which aredctachably connected at their lower ends by bolts g2, or by othersuitable means. to links g connected to the outer ends of the valves Itsurrounding the push rods in the guidel pockets serve to hold the rodsagainst the cams and to return the valves to the position from whichthey are rocked in one direction by the cams. The upper ends of the rodsproject from the guide pockets into the crank chamber for engagementwith the cams, while the lower' ends of the rods extend from the guidepockets outside of the pump casing forA connection with the outer endsof the valves. By this arrangement the cams and upper ends of the pushrods are inclose'd in the pump casing where they are protected from dustand kept thoroughly lubricated by the oil running down from thecrank-shaft bearings, hut the connections between the lower ends of therods and the valves are located outside of the casing so that'thc valvescan be readily disconnected from the rods and pulled endwise out of thevalve chamber .E2 without disturbing the push rods or other parts of thepump when this is necessary for cleaning the valves, or for any otherreason.

rllhe operation of the pump is as follows: The cams G G are arranged onthe crank shaft as shown in Fig. 4, which indicates their position whenthe pistons are at the ends of their strokes, and the ports e and e areclosed by the valves. The crank shaft turns in the direction indicatedby the arrow in Fig. 4. The cam G rocks the valve E and starts to openthe porte to the inlet passage f as soon as the piston B starts on itsup stroke, and the cam is so shaped that thevalve is opened Wide whenthe piston has moved but a very short distance and is held wide openuntil the piston nearly reaches the end of its up stroke, When the camallows the valve to be closed gradually by its spring h, the valve notbeing fully closed, however, 'until the piston starts l'on its downstroke. During the down stroke of thepiston the cam allows the spring hto rock the valve farther in the return direction so as toy graduallyopen the port e to the outlet passage f. As the piston approaches theend of its down stroke the cam moves the valve to again close theoutlet'port e. The valve for the other cylinder is operated in the samemanner. By thus holding the ihlet open until the piston has actuallybegun its return stroke the inertia of the incoming air is utilized totill the cylinder, and as the valve does not open the outlet port euntil the piston reaches that point in its down stroke at which the airin the cylinder has been compressed to atmospheric pressure, there is notendency for the air to rush into the cylinder when the outlet is openedand thereby increase the work of the pump.

The cam permits only a very gradual return movement of the valve by thespring, and the cam and spring-operated valve work very smoothly at highspeeds of the pump.

By the described construction of the pump .with the valves in the baseand the pipes connecting with the base section independently of thevalves, the crank shaft, pistons and valve-operating devices are veryaccessible and can be examined and cleaned at any time by simplyremoving the loose cover plate at, and if it is necessary to remove thecrank shaft and pistons it is only necessary to detach the top sectionZ2 of the casing and lift the shaft and pistons out of the cas# ing.This could not be done if the pump were inverted or arranged withthevalves and pipe connections at the top of the casing. To remove thevalves it is only necessary to detach their links from the push rods andslip the valves endwis'e out of the openended valve chamber, and neitherthe pipe connections nor any other parts of the pump have'to bedisturbed. l,

In the pump shown, the crank shaft is provided with tight and loosepulleys l I', the latter being journaled on a detachable extension ofthe shaft consisting of a sleeve K secured to the end of the shaftproper by a cap screw /c and end plate 7c. When the loose pulley is notrequired, the extension sleeve K is detached and the end plate 7c issecured to the end of the crank shaft by a short screw. Thisconstruction may be employed or not, as desired.

L represents an 'oil drip pan which vis provided beneath the basesection a. ot' the casing.

l claim as my invention:

l. ln a pump, the combination of a casi ng provided with a cylinder andwith connections for the Huid at the base portion of the pump, a pistonin said cylinder', a crank shaft removably journaled in the v casingabove the cylinder and connected to the piston, a valve for the pumpremovably seated, in the base portion thereof, an operating device forsaid valve mounted on the crank shaft, and aconnecting` device actuatedby said device on the crank shaft and detachably'connected to the valveoutside of theA casing, whereby the crank shaft and piston and the yalvecan be removed from the pump tifithout disturbing said fluid coni stlniovably seated in the base portion thereof,-

an operating cam for said valve mounted on the c ank shaft inside of thecasing, and a pushiljod mounted on said casing and having` fits upperend enterinpr the easing for. engagement with said cam and its lowerend, extending outside of the casing` and dei tachably connected tothevalve, whereby the crank shaft and pistonand the valve can be removedfrom the pump Without disturbing said fluid eomiections, and said valvecan be removed when detached from said push rod Withoutdisturbingr theother parts of the pump, substantially as set forth.

3. ln a pump, the combinati-on of a easing provided with uprightcylinders, -`and with fluid connections at the base portion of the pump,pistons .in said cylinders,U a crank shaft removably journaled in thecasing above the cylinders and connected to the pistous, inlet andoutlet valves removably seated in the base portion of the pump, op.-

erating cams for said Valvesmounted on the opposite ends of said crankshaft inside of the casing, and push rods mounted in bearii'igs on theopposite sides ofthe casing and having their upper ends entering thecasingfor engagement with said cams and their lower ends extendingoutside of the easing and detachably connected to the outer ends of saidvalves, whereby the crank shaft and pistons and said valves can beremoved from the pump without disturbing said fluid connections, andsaid valves can be removed when detached from said push rods Withoutdisturbingthe other parts of the pump, substantially asset forth.

et. n a pump, the combination of a casing prtwidcd with yparallelupright cylinders, pistons in the cylinders, a crank .shaft jeunytheiremo'val of the crank shaft and 11a-led in the casing` abovec-thecylinders and connected t6 the pistons, the casing;1 having an upperpart `vhich is detachable to permit pistons, inletfavnd outlet valvesfor th cylinders ren'ioxfztb'ly seated in the base port-ion of the"casing, operating cams for said valves mounted on the opposite ends ofthe crtnk shaft inside of the casing, push rodsyt-arranged at theopposite sides of said easing which are actuated by` said cams and aredetachably connected to said valves. and pipe connections for the pumpat the base thereof, substantially as set forth.

5. In a pump, the combination of a easingl having' detachably connectedtop, bottoni and intermediate sections, said intern'xediate 'sectionhaving` a cylinder, and said bottom section ha ving an open-ended valvechamber, a piston in the cylinder, a crank shaft journaled in thecasing' above the cylinder and being remo 1able(.therefrom by detachingthe top section of the casino, an oscillating valve in said valvechamber andl removable through the open end thereof, an operating,` camfor said valve on the crank shaft, a push rod which is actuated by saidcam and is detachably connected outside of the casing with said valve,andI pipes connecting with said base section] of the easing, IWl'lerebythe crank shaft, piston and valve can be removed without disturbing thepipe connections, substantially as set forth.

lWitness my hand, this 19th day of May, 1909'.

l CHARLES B. DALZELL.

